1. Field of the Invention
The present invention is related to a connector assembly having contacts with high density arrangement so as to interconnect two printed circuit boards or modularized circuit board assemblies, especially to a connector assembly having a simple and facilely assembled mounting interface for connecting daughter board assembly to a motherboard.
2. Description of Prior Arts
In a specialized backplane assembly of a computation or communication device, a primary circuit board is used to connect other intermediate circuit boards or extension cards to achieve different electronic functions or performance. In most situations, more extension cards are needed to connect to the primary circuit board via one of the intermediate (secondary) circuit boards/extension cards in order to provide repeated electronic function. It is understood that high density interconnection between the primary circuit board and the one intermediate circuit board will become necessary so that all the extension cards mounted on the one intermediate circuit board can effectively and efficiently communicate with the primary circuit board via the high density interconnection. Conventionally, a set of plug and receptacle connectors is considerable to be adapted for connecting the primary circuit board and the one intermediate circuit board. At least three interfaces have to be considered in this interconnection, a mating interface between the plug and receptacle connectors and two mounting interfaces for the plug and receptacle connectors respectively to circuit boards where they are seated. Czeschka U.S. Pat. Nos. 4,959,024 and 6,129,591, Niitsu et al. U.S. Pat. No. 5,735,696 and Wang U.S. Pat. No. 5,919,063 all show different interfaces of a plug connector and a receptacle connector for mating and mounting. Obviously, both plug and receptacle connectors have contacts with a specialized shape of their own. To guarantee the reliable engagement between the mating plug contact and receptacle contact, enough engaging area and interaction force should be provided by the contacts when the connectors are mated. And a reliable mounting joint, usually a soldered one, between ever plug or receptacle contact and circuit board is very important too for better electrical performance. To sum up, interconnection of two separate connectors, including a plug and a receptacle, needs twice the manufacturing and assembly processes to make the component connectors and double the processes to mount them onto the corresponding circuit boards. Therefore, the conventional connector designs will have a high cost for the type of application.
Additionally, in the compact arrangement of the intermediate circuit board, limited space is available to receive electronic components and smaller pitches between contacts restrain possible variations of size and shape of the connectors of their parts, especially the intermediate circuit board having lots of extension cards installed thereon. Thus, simplified connector parts are preferred to reduce the occupied space of the connectors. Obviously, complicated mating of mounting mechanism the conventional plug and receptacle connectors have is not the best choice for a compact arranged intermediate circuit board.